Yamaha DTXpress/DTXplorer/DTXtreme

I have a bell pad that I don't use because the only place I know how 
to mount it is on top of the ride cymbal pad - where hitting it 
vibrates through and sets off the ride and rim sound. So I'm trying 
to find out how to mount it somewhere else on the DTXpress frame. Can 
anyone offer me a hint on how to do this? The attachments that came 
with the bell pad do not seem to include anything that will help.